1893.1 227 



ON THE GENUS HALOBATES, ESCH., AND OTHER MARINE 

 HEMIPTERA. 



BY JAMES J. WALKEE, E. N., P. L. S. 



The genus Saloiates is one of the most remarkable and interesting 

 forms of the Order Hemiptera, and, indeed, of all insects, both from 

 its truly oceanic habitat (unique, so far as is known at present, among 

 the class Insecta), and from the very curious structure and habits of 

 the various species. Since the expedition of von Kotzebue round the 

 world in the Russian ship "E-urick" early in the present century, 

 when three species were described by Eschscholtz, the founder of the 

 genus, from the examples taken by the naturalist Chamisso, these 

 little creatures have attracted the attention and interest of nearly 

 every observant voyager. A literature of some considerable extent 

 has grown up respecting them, and this has been brought together in 

 the well-known and able "Eeport on the Pelagic Hemiptera'''' (Zoology 

 of the Voyage of H.M.S. " Challenger," part xix, 1883), by Dr. F. 

 Buchanan White, P.L.S., to which I owe much valuable aid in the 

 compilation of these notes. 



In the late surveying voyage of H.M.S. " Penguin " in Australian 

 and Chinese waters, I paid a good deal of attention to the habits and 

 distribution of these insects, and I propose to give hei*e a brief sum- 

 mary of my observations, prefaced by those made in a former voyage 

 to the Pacific in H.M.S. " Kingfisher." 



Crossing the tropical Atlantic in this latter vessel in 1880, 1 kept 

 a good look out for the characteristic species of that ocean, H. 

 Wiillerstorffi, Frauenf ., but neither on this occasion, nor on my return 

 voyage across the Atlantic in 1884, did I observe a single specimen of 

 Salobates. The first time that any came under my notice was on 

 October 6th, 1881, in the Grulf of Panama, but the ship was then 

 steaming at six knots per hour, so I was unable to obtain them. Nor 

 did another opportunity occur until more than a year afterwards, when 

 we were on a voyage from San Erancisco to Callao. On November 

 26th, 1882, we were becalmed for a short time in lat. 8° 12' N., long, 

 101° 46' W., when I saw a good many specimens on the surface of the 

 sea, and caught six or seven from the ship's gangway (Ent. Mo. Mag., 

 vol. xix, p. 278). These were the widely distributed Pacific species, 

 H. sericeus, Esch. On a voyage from Callao to the Marquesas Islands, 

 in February and March, 1883, Halohates was frequently observed in 

 the open ocean whenever the usually steady south-easterly breeze fell 

 light for a short time. Several specimens were seen on Eebruary 27th 



